The conflict has left about 380,000 dead, according to the UN, either directly in the fighting or as a result of famine and disease.
2014: HUTHIS TAKE CAPITAL
Huthi rebels from the Zaidi Shiite minority in northern Yemen seize the capital Sanaa in September 2014.
Backed by Shiite heavyweight Iran, they ally themselves with soldiers loyal to ex-president Ali Abdullah Saleh, who was toppled in a 2011 uprising.
They also overrun the lifeline Red Sea port of Hodeida.
In February 2015, President Abedrabbo Mansour Hadi flees to the second city Aden, on Yemen's south coast.
2015: SAUDIS STEP IN
A coalition led by Iran's bitter enemy Saudi Arabia and the United Arab Emirates enters the conflict in March 2015 with airstrikes on the rebels.
Washington says it is contributing logistics and intelligence.
As the rebels advance on Aden, Hadi flees to Saudi Arabia.
The coalition's intervention helps pro-government forces secure Aden.
In October, coalition forces take control of the Bab al-Mandab strait at the southern gates of the Red Sea, one of the world's busiest and most strategic waterways.
2018: BATTLE FOR KEY PORT
In June 2018, government fighters backed by coalition ground forces launch an offensive to retake Hodeida, a key entry point for humanitarian aid.
In December, following negotiations in Sweden, the UN announces a ceasefire in Hodeida.
But it is marred by clashes between rebels and pro-government soldiers around the city.
SEPARATISTS FLEX MUSCLES
The anti-Huthi camp is divided between southern separatists and northern unionists loyal to Hadi's government.
The separatists occupy the presidential palace in Aden in January 2018, before Saudi and Emirati forces intervene.
In August 2019, Emirati-backed separatists again clash with unionist troops.
Riyadh negotiates a power-sharing agreement and the formation of a new government.
2019: SAUDI OIL HIT
The rebels escalate their attacks on Saudi Arabia, using drones and missiles.
A major hit on September 14, 2019 on the giant Abqaiq oil processing plant and Khurais oil field halves the kingdom's crude output.
Riyadh and Washington accuse Iran of being behind the attack, which it denies.
2021: NEW ESCALATION
In February 2021, the US ends its support for the coalition's military operations and removes the Iranian-backed Huthis from a "terrorist" blacklist.
Shortly afterwards, the rebels resume an offensive to seize oil-rich Marib province, the government's last northern stronghold.
2022: REBELS TURN ON UAE
On January 3, 2022, the rebels seize an Emirati-flagged vessel in the Red Sea.
A week later, pro-government forces claim to have retaken Shabwa province, which neighbours Marib.
On January 17, a rebel drone and missile attack on an oil facility in Abu Dhabi kills three, the first deaths reported in the United Arab Emirates.
The Saudi-led coalition carries out retaliatory airstrikes on Yemen's capital Sanaa.
US SENDS WARSHIP, FIGHTERS
In early February, Washington announces it is sending the destroyer USS Cole and fighter jets to Abu Dhabi to bolster its defences.
On February 28, the UN Security Council expands an arms embargo on Huthi leaders to all the rebels.
HUMANITARIAN DISASTER
The situation in Yemen is regularly described as the world's worst humanitarian crisis.
In a March 14 update, the UN says 17.4 million of Yemen's 29 million people are facing high levels of acute food insecurity.
